1 /*
   2  * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.nio.file.*;
  25 import java.nio.file.attribute.*;
  26 import java.io.IOException;
  27 import java.util.*;
  28 
  29 /**
  30  * Unit test for Files.walkFileTree to test SKIP_SIBLINGS return value.
  31  */
  32 
  33 public class SkipSiblings {
  34 
  35     static final Random rand = new Random();
  36     static final Set<Path> skipped = new HashSet<Path>();
  37 
  38     // check if this path's directory has been skipped
  39     static void check(Path path) {
  40         if (skipped.contains(path.getParent()))
  41             throw new RuntimeException(path + " should not have been visited");
  42     }
  43 
  44     // indicates if the siblings of this path should be skipped
  45     static boolean skip(Path path) {
  46         Path parent = path.getParent();
  47         if (parent != null && rand.nextBoolean()) {
  48             skipped.add(parent);
  49             return true;
  50         }
  51         return false;
  52     }
  53 
  54     public static void main(String[] args) throws Exception {
  55         Path dir = Paths.get(args[0]);
  56 
  57         Files.walkFileTree(dir, new SimpleFileVisitor<Path>() {
  58             @Override
  59             public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
  60                 check(dir);
  61                 if (skip(dir))
  62                     return FileVisitResult.SKIP_SIBLINGS;
  63                 return FileVisitResult.CONTINUE;
  64             }
  65             @Override
  66             public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
  67                 check(file);
  68                 if (skip(file))
  69                     return FileVisitResult.SKIP_SIBLINGS;
  70                 return FileVisitResult.CONTINUE;
  71             }
  72             @Override
  73             public FileVisitResult postVisitDirectory(Path dir, IOException x) {
  74                 if (x != null)
  75                     throw new RuntimeException(x);
  76                 check(dir);
  77                 return FileVisitResult.CONTINUE;
  78             }
  79         });
  80     }
  81 }